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And
its safer and better tolerated as well
In the largest randomized, multicenter, double-blind
trial to compare St John's Wort (hypericum perforatum) with a tricyclic
antidepressant, the herb was found to be therapeutically equivalent to
the drug (imipramine) in treating patients with mild to moderate depression.
Actually, the
herb outperformed the drug in every clinical test used to measure depression,
although the differences were not statistically significant in most cases.
In addition, it was found to have a superior safety profile and caused
less adverse reactions.
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A total of 324 patients at 40 different outpatient
clinics in Germany were randomly assigned to treatment with either
hypericum extract in tablet form or imipramine.
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St. Johns Wort was better tolerated than imipramine
and fewer patients on it withdrew as a result of adverse effects.
For example:
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In a 5-point scale used by participants to measure
tolerability (1-excellent, 5-poor) the herb was rated on average 1.67
and the drug was rated on average 2.35.
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Adverse events occurred in 39% of patients taking
St. John's Wort versus 63% of patients taking imipramine.
The study's authors conclude that Hypericum extract
is as effective as imipramine, but its advantage as a first line treatment
is its superior safety profile.
In a letter published on the journals web site in
response to this study, Ron Law, Executive Director of the National Nutritional
Foods Association of New Zealand, states "This is the 33rd randomized
clinical trial reporting that the dietary supplement St John's Wort is
both extremely safe and extremely effective. How much more evidence is
needed ... "
He also cites a
web site with a good source of information on possible interactions
between St. John's Wort and various drugs.
Dr. Paul Kepkay, MD, a retired Internist, states
that the study was conducted in Germany, where there are much better controls
in place for herbs and physicians have more experience in their use, as
compared to the US and Canada. Therefore, while not disputing the superior
results of St John's Wort in the study, he maintains that these can't
be transposed elsewhere.
In comments to the Optimal Wellness Center, Dr.
Sam Benjamin, Medical Director of Mariposa
Botanicals, states that while the quality of European products may
be somewhat better, in general, due to some controls in place, there are
many quality control initiatives that are being undertaken this side of
the Atlantic by quality companies.
For example, according to Dr. Benjamin, quality
control testing should be done by quality independent laboratories, rather
than only in-house labs, which can be very biased. Some of the things
which are important to test for are:
- Heavy Metals
- Microbiological Contamination
- Potency
- Insure proper raw materials are being used
"Standardization"
is a concept that has both its virtues and its faults, according to Dr.
Benjamin. On the plus side, it does help to get a product with consistent
levels of one particular component. Unfortunately however, often the so-called
"active" ingredient of a particular herb is either not known
or several components may act synergistically. "The marker compounds
may or may not even be the active compounds" says Victor Werbin,
who is in charge of production and quality at Mariposa.
"Therefore, as much as we can at Mariposa
we use 'standardization' as a way of assuring consistency, but we try
as much as possible to capture the whole plant. In the future we will
be identifying 4-6 components of each plant as a way of maintaining consistency.
We will set up standards for acceptable variation of these components.
However, we will not "concentrate" or artificially "engineer"
the product to meet 'standardization'" states Dr. Benjamin.
Lastly, with all of the high-tech testing methods
available, it is important not to forget about the simple methods, such
as using the five senses. "I still look, taste, smell and feel these
things. One look and taste can eliminate the need for testing an inferior
material," says Mr. Werbin.
British Medical Journal
September 2, 2000;321:566.
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